Paint spraying masks and method of making same



E. L. RICH 2,3 3

PAINT SPRAYING MASKS AND METHOD OF MAKING SAME Dec. 9, 1958 Filed Jan. 15, 1954 INVENT'OR d arm/A M mw/rw% ATTORNEYS 2,863,384 Patented Dec. 9, 1958 ice PAINT SPRAYIN G MASSKS AND METHOD OF MAKING SAME Edward L. Rich, Bay City, Mich. Application January 15, 1954, Serial No. 404,343

7 Claims. (Cl. 101-127) This invention relates to masks or shields for covering areas contiguous to those to be sprayed with paint or to be vacuum plated and to methods of constructing the same.

It is a particular object of the instant invention to provide a novel production type mask for covering certain designated ornamental portions of steel stampings, die casings, plastics and the like, in which figures, letters, emblems and embossed designs of various kinds are preformed, and to provide a new method of constructing such a mask.

As is well known in the art, spray masks as these masks are commonly termed, are conventionally formed by electroplating relatively thick coatings of copper or nickel on an emblem plate to be masked and thence cutting and filing away the portions of the design which are to receive the paint in the plate thus formed to the exact specifications. Such masks require from three to five days to manufacture and when once damaged, cannot be repaired and must be discarded.

One of the prime objects of my invention is to pro vide a mask which can be fabricated in a few hours in a simple and easy manner and thus permits the increase of plant production and the saving of considerable labor cost.

Another object of the invention is to provide a mask which can 'be bent back into shape when dented or damaged, or can be readily reshaped to compensate for wear or to mask areas which vary in location or size as much as fifteen thousandths of an inch with the areas to which the mask was originallyforrned.

A further object of the invention is to providea novel method of fabricating spray masks which requires no expensive electro-forming equipment or the like, and which produces a production mask of strong and durable construction.

Another object of the invention is to provide a spray mask which can be formed to mask very small areas of intricate configuration and which is well-suited to masking several areas at the same time, to thus keep the number of masks required to spray a given emblem plate at a minimum.

A further object of the invention is to design a highly efiicient spray mask which saves wipin operations and permits an increased number of emblems or designs to be sprayed before cleaning the mask.

A still further object of the invention is to design a mask which is easy to use and can be economically employed in the mass production decorative spray painting of emblems, name plates, and the like, the mask minimizing costly rejects and permitting maximum production per labor hour.

With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportion, and minor details of construction, without departing from the spirit, or sacrificing any of the advantages of the invention.

In the drawing:

Fig. l is a perspective view of a plastic emblem which is to be spray painted.

Fig. 2 is a top plan view of a base plate in which an opening has been cut, illustrating the first step in fabricating a mask or shield for the emblem plate shown in Fig. 1.

Fig. 3 shows a relatively thin, pliant, and workable shim-like sheet of material applied to one face of said base plate over said opening.

Fig. 4 is an elevational, sectional view taken on the line 44 of Fig. 3.

Pig. 5 is an elevational, sectional view taken on the line 5-5 of Fig. 6, showing the partially formed mask of Figs. 3 and 4 located with respect to the emblem shown in Fig. l, the pliant shim having been worked down into the depressed areas of the emblem plate.

Fig. 6 is a top plan view thereof.

Fig. 7 is a view similar to Fig. 4 of the mask only, showing bridging connecting the raised central portion and the base plate.

Fig. 8 is a view similar to Fig. 7 in which the depressed portions of the mask have been cut out.

Fig. 9 is a similar view showing the completed mask mounted on the plastic emblem ready for the paint spraying operation.

Fig. it] is a view of a modified mask in partially completed form, as used on a slightly different emblem plate where itis desired to mask another area, illustrating how sample masks can be quickly fabricated for customer inspection and trial.

Referring now more particularly to the accompanying drawing in which 1 have illustrated preferred embodiments of my invention, and more particularly to Figs. 19, a letter P generally designates a plastic emblem plate such as may be applied to various appliances and products to designate the product or manufacturer thereof. For the sake of convenience, I have shown the emblem plate P in a simple form in which a portion it of the plate is depressed to form a letter 0. In order to spray paint on this portion it only, or to vacuum plate the same, it will be obvious that the slightly sloped marginal side walls 11 of the depressed areas 110 and the central portion 12 of the letter must 'be masked or shielded.

Figs. 29 illustrate a novel method of fabricating a spray mask which can ge employed in the mass production spraying of emblem plates of this nature. in Fig. 2 is illustrated a base plate 13 which may be formed of a suitably rigid material such as copper plate or the like of sufficient thickness so that it is substantially inflexible and cannot be readily dented or bent. An opening 14 is roughly cut through the plate 13 with a tool such as a jewelers saw, the opening being cut slightly larger than the letter C) in the emblem plate P. The opening 14 should, for good results, be about the width of a saw a blade larger perimetrally than the letter 0, or about .02 inch larger. A sheet 155 of a flexible, tractile material is then soldered or otherwise fixed to one face of the plate 13 as shown in Figs. 3 and 4, and it will be observed that the sheet 15' is relatively thin in comparison to the base plate 13 which for purposes of this specification will be ermed relatively thick. I have found that plates 13 which are from JIM-.08 inch in thickness are suitable for the purpose and that good results are obtained when the sheet i5 is from .003.01O in thickness.

The sheet 15 may be cut from what is known as yellow brass shim stock which should be annealed so that it is tractile and workable. I have found that a sheet of this material whose thickness is measured in thousandths of an inch is sufiiciently pliant and ductile so that it can be very readily worked into the depressions of the plate to be masked, as has the sheet 15 in Figs. 5 and 6. Prior to this operation, of course, it was first necessary to locate the partially completed mask on the emblem plate P and clamp it thereto in a manner which will immobilize it during the forming operation, but permit the ready removal of the mask after the sheet 15 has been formed to the portions and 11 of the emblem plate with a burnishing tool or the like. It is convenient to scribe the outline of the plate P on the plate 13 when the opening 14 is scribed for cutting so that the location of the plate P with relation to the mask thereafter will be easy. The portions of the sheet 15 corresponding to the portions 10, 11 and 12 of the emblem plate P are designated 16, 17 and 18 respectively. Since the forming operation is a cold working operation, the sheet 15 stiffens somewhat and develops a resiliency which tends to retain it in the exact shape to which it has been formed.

The mask or shield can then be removed from the plate P and suitable bridging wire to support various portions of the sheet 15 fixed thereto. In Fig. 7, a bridging wire 19 spans the letter O, the ends thereof being soldered to the base plate 13 and the central portion thereof to the central portion 18 of the sheet 15 to support the same. The bridging wire 19 is formed from fine wire stock which is sufiiciently sturdy and rigid to hold isolated portions of the mask firmly in position without shadowing the area to be sprayed when the paint is sprayed on, so that portions thereof are not painted. In the instant case, it is desired to paint the portion 10 of the emblem plate P and accordingly, the depressed portion 16 of the sheet 15 is cut out; however, if it had been desired to paint the portion 12 of the plate P, obviously, the bridging wire could be omitted and the central portion 18 of the sheet 15 cut out. If the portion 16 of the mask is to be cut out, the edges of the slightly inclined walls 17 are ground off so that they terminate just short of the depressed area 10 of the plate P (see Fig. 9), when the mask is applied thereto, thus permitting the entire surface of the area 10 to be reached by the paint. In some instances where it is desired to paint the lower portions of the marginal side walls 11 of the plate P to provide the depressed letter or letters with a visual depth, the Walls 17, of course, will be terminated far short of the area 10. In cases in which only the portion 18 of the mask is to be cut away, the edges of the contiguous side walls are rolled over the edges thereof to prevent the entrance of paint thereto.

Trimming and smoothing of the various edges or lips of the mask after the desired portions thereof have been cut out, of course, can be accomplished very rapidly with conventional grinding wheels. Often the inner portions of the lips will be reinforced with solder as at S in Fig. 9.

In operation, the mask is applied to an emblem plate P as in Fig. 9 and paint may be sprayed on the area 10.- For convenience sake, the mask will be described as employed with paint spraying equipment, but it will be obvious that the mask also finds use with vacuum plating equipment andthe like. The painter thence merely removes the mask and applies it to the next plate and it will be obvious that one person can process a great many emblem plates in a given amount of time. Since several masks or shields are fabricted to ech prticulr type of plate, the processing can be continuous even though the masks need be cleaned periodically. As will be obvious from an inspection of Fig. 8, the depending portions 17 of a mask will be dented and bent ocassionally when the mask is inadvertently rested thereon or during handling of the mask, and with applicants novel mask, it is a simple matter to place the mask on the emblem plate and use the burnishing tool to bend back the damaged portions of the sheet 15 which tend to return to their cold worked shape. y

In some instances, also, the final batches of emblem plates vary slightly in dimension with the plate with which the mask was made, and in many cases applicants mask can be stretched to adapt to the new plates, the material 15 being sufficiently ductile so that it may be stretched as much as fifteen thousandths of an inch. Conventional masks which are relatively thick and have substantially no ductility, must be discarded and new masks fabricated where the model and final plates diifer even slightly due to casting conditions. For this reason, also, the bridging Wires 19 are sufiiciently flexible so that the cap portion 18 of the mask can be adapted where the variance between the model and final emblem plates is not too great.

Often a customer will submit an emblem plate and order a temporary or preliminary mask which can be tested to determine if it will do a satisfactory job. In Fig. 10 is shown a sheet of shim material 20 which is applied to an emblem plate P without fixing it to a base plate. This sheet 20, of course, is larger than the sheet 15 so that it can be conveniently handled, athough of the same thickness, and once it has been formed to shape, a coating of solder 21 is applied to various areas thereof to strengthen it. Except for the employment of a base plate and this strengthening operation prior to cutting out the desired portions of the mask, the mask shown in Fig. 10 is fabricated and used in the same manner as is the mask illustrated in Figs. 2-9; however, obviously, it could be used only a few times. In Fig. 10, the portion 12 of the plate P which it is desired to paint or plate, is slightly depressed and the Walls 17 adjacent thecentral portion of the mask which is cut out are rolled over the edges thereof as at 22.

It will be apparent to those skilled in the art that I have perfected a novel mask and a novel method of forming spray masks which is far superior to known masks and methods of forming the same. It is to be understood that various equivalent changes may be made in the mask or in the manner of constructing spray masks here described, without departing from the spirit of the invention or the scope of the appended claims. In all cases ,the descriptive matter is to be interpreted as illustrative rather than limiting or confining.

What I claim is:

1. The method of constructing a spray shield to mask out certain areas of an indented configured surface which are at different levels than other areas which are to remain exposed which comprises, cutting an opening of slightly larger size than the spread of said areas through a rigid plate of substantial thickness, fixing a sheet of relatively thin, ductile, annealed brass on the face of said plate to cover said opening, mounting said plate on said surface with said brass sheet over said areas and adjacent thereto, cold working the brass sheet into the depressed areas of said surface so that the sheet conforms to the surface which it overlies and stiffens and develops a resiliency which tends to return to said shape if it becomes dented or bent, and cutting out the portions of the sheet corresponding to the areas of the surface which are to be exposed for painting.

2. The method of constructing a spray shield to mask out a certain area of an indented configured surface which is at a different level than other areas which are to remain exposed which comprises; fixing a sheet of relatively thin, ductile brass in place overlying and adjacent to the said areas of said surface; cold working the brass sheet into the depressed areas of said surface so that the sheet conforms to the surface which it overlies and stifiens and develops a resiliency which tends to return it to said shape if it becomes dented or bent; and cutting out the portions of the sheet corresponding to the areas of the surface which are to be exposed for painting.

3. The method of constructing a spray shield to mask out a certain area of an indented, configured surface which is at a different level than other areas which comprises; fixing a sheet of a relatively thin, ductile material of a type which stiffens and develops resiliency when it is cold worked in place overlying and adjacent to the said areas of said surface; cold working the sheet by drawing it into the depressed areas of said surface so that the sheet conforms to the surface which it overlies and stiifens and develops a resiliency which tends to return to said shape if it becomes dented or bent; and cutting out the portions of the sheet corresponding to the areas of the surface which are to be exposed for painting.

4. The combination defined in claim 3 in which said material is of the type to which solder will adhere, and which adds the step of reinforcing the sheet by applying a thin coating of solder to portions of said sheet.

5. The method of constructing a spray shield to mask out certain areas of an indented configured surface which are at different levels than other areas which are to remain exposed which comprises; cutting an opening of slightly larger size than the spread of said areas through a rigid plate of substantial thickness; fixing a sheet of relatively thin, ductile material of a type which stiffens and develops resiliency when cold worked on the face of said plate to cover said opening, mounting said plate on said surface with said sheet over said areas and adjacent thereto, cold working the sheet into the depressed areas of said surface so that the sheet conforms to the surface which it overlies and stilfens and develops a resiliency which tends to return to said shape if it becomes dented or bent, and cutting out the portions of the sheet corresponding to the areas of the surface which are to be exposed for painting.

6. A spray shield for masking out certain areas of an indented, configured, portion of a surface, which portion includes areas at different levels, comprising; a very thin, ductile sheet for mounting on said surface over said areas, with portions of said sheet drawn into the depressed areas so that said sheet presents an indented surface with areas at different levels conforming to said portion of the first mentioned configured surface, said latter portions being stiff and having a cold working developed resiliency which returns them to said indented shape if they become dented or bent; said sheet having openings therein conforming to certain areas of said surface which are to remain exposed.

7. The combination defined in claim 6 in which said ductile sheet comprises a brass sheet.

References Cited in the file of this patent UNITED STATES PATENTS 5,511 Foster Apr. 8, 1848 316,225 Beck Apr. 21, 1885 318,943 Beck June 2, 1885 329,476 Miller Nov. 3, 1885 445,241 Croskey et a1. Ian. 27, 1891 682,769 Thorpe Sept. 17, 1901 789,153 Horn et al May 9, 1905 817,608 Adames Apr. 10, 1906 1,481,956 Carufel Jan. 29, 1926 1,573,082 Madden Feb. 16, 1926 1,600,229 Heidman Sept. 21, 1926 1,674,680 Buttner June 26, 1928 1,822,986 Bauer Sept. 15, 1931 2,622,990 Rinck et al Dec. 23, 1952 

